The Flexural Efficiency and Effectiveness of Geometrically Interlocked Layered Wood-Plastic Composite Beams

International Journal of Civil Engineering

© 2026 by SSRG - IJCE Journal

Volume 13 Issue 3

Year of Publication : 2026

Authors : Eduard Darrel P. Rivera, Dexter Hansel C. Apnoyan

10.14445/23488352/IJCE-V13I3P124

How to Cite?

Eduard Darrel P. Rivera, Dexter Hansel C. Apnoyan, "The Flexural Efficiency and Effectiveness of Geometrically Interlocked Layered Wood-Plastic Composite Beams," SSRG International Journal of Civil Engineering, vol. 13,  no. 3, pp. 335-351, 2026. Crossref, https://doi.org/10.14445/23488352/IJCE-V13I3P124

Abstract:

The concept of topological and geometrical interlocking is an atypical method of assembling built-up sections and composites. It is commonly demonstrated in traditional woodworking techniques, where components are joined without mechanical fasteners or chemical adhesives. The paper explored its structural application to modern materials and construction practice by examining three two-layered wood-plastic composite beams whose components were solely interlocked by 45-degree grooves or notches. The beams were produced as test specimens and were analyzed for their yielding and rupturing flexural effectiveness and efficiencies. The effectiveness compares their full composite theoretical flexural strengths to their actual values, while the efficiencies determine their capacity to retain full composite action during bending. The theoretical calculations incorporated classical elastic and plastic beam theories, and the actual values were determined by a standard three-point bending test. The analysis showed that the beam specimens achieved, on average, 66.98 percent of their theoretical full composite flexural strength at yield and 55.59 percent at rupture while maintaining an average full composite behavior of 78.53 percent at yield and 59.55 percent at rupture. Results of the experiment described the beam specimens as unable to retain constant efficiency and only able to realize subpar flexural strengths. While the evidence concluded them to be partial composites, the analyzed data showed that the peaks in efficiency and effectiveness generally occurred during yield and then continuously decayed post-yield until rupture.

Keywords:

Effectiveness, Efficiencies, Full composite, Geometrical, Topological interlocking.

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